


me and my cousins and you and your cousins

by mozaikmage



Category: Haikyuu!!, モブサイコ100 | Mob Psycho 100
Genre: Crossover, Gen, Study Sessions, this is very silly but I really wanted it to exist so it does
Language: English
Status: Completed
Published: 2018-12-01
Updated: 2018-12-01
Packaged: 2019-09-05 04:40:49
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,578
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16803826
Author URL: https://archiveofourown.org/users/mozaikmage/pseuds/mozaikmage
Summary: Kageyama Tobio's cousins come to visit during summer vacation.His cousins have supernatural powers.Naturally, Hinata wants to meet them.





	me and my cousins and you and your cousins

**Author's Note:**

> the title's from the vampire weekend song "cousins"  
> I can't believe there's only one fic w/this premise already on this site. you're all cowards

It’s the last week of Tobio’s first summer break in high school. The five Karasuno first years are crammed together around a table in Yachi’s apartment working on their summer break assignments. Or, Tobio and Hinata are working on their assignments after procrastinating for a month, Tsukishima’s making fun of them, and Yamaguchi and Yachi are trying their best to help.

Tobio’s phone vibrates and he checks the notification with a sigh. “I have to go. My cousins are visiting and my mom wants me to eat dinner with them,” Tobio says. 

Hinata drops his pencil. “You have cousins?”

“Everyone has cousins, dumbass.” 

“Not everyone,” Tsukishima butts in.

“Well, I have two, and they’re visiting for the rest of the break, so. See you guys later. Thanks for inviting me, Yachi-san.” Tobio shoves his papers into his bag, nods at Yachi, and is putting on his shoes when Hinata jumps in front of him.

“I wanna meet them!”

Tobio squints. “Why.”

“Because they’re your cousins! What if they’re super good at volleyball too!”

“They’re in middle school, they can’t be  _ that _ good.” Tobio pauses in the middle of tying his shoelace. “I think Ritsu’s athletic, but Shigeo’s awful at sports. He does… other stuff.”

“What kind of other stuff?”

Tobio throws his bag over his shoulder. “You would not believe me if I told you.”

“Well now I  _ really _ have to meet them!” 

“I didn’t say you could come, dumbass, what — ”

Hinata grabs his stuff and practically runs out the door.

“Thanks for having us, Yachi-san!”

“Hinata, you still have two pages of math problems left!” 

“Sorry about Hinata, he invited himself over,” Tobio explains to his mom when she opens the door to see her son accompanied by an excitable orange child. She offers Hinata some curry too.

The Cousins are sitting at the dining room table with Tobio’s dad, plates of curry cooling in front of them as they wait for Tobio to sit down. They look a little like Tobio, Hinata supposes. 

“Ritsu, Shigeo, this is Hinata, my volleyball teammate,” Tobio says. “Hinata Shouyou.” 

Hinata bows. “Nice to meet you!”

The siblings stare. “I didn’t know Tobio-nii-san had friends,” Ritsu says, in a polite and conversational tone of voice. “I’m Ritsu.”

“I’m Shigeo,” the other one says, sounding distracted. 

Hinata watches with wide eyes as the spoon in Kageyama Shigeo’s hand twists into a pretzel shape and drops curry and rice all over the dining room table. The Kageyama family just sighs in unison, like this is a normal everyday occurrence.

“Your mother told me you’ve gotten better at controlling that, Shigeo-kun,” Tobio’s father says, passing a napkin to Shigeo.

“Sorry,” Shigeo mumbles. 

Ritsu wiggles his fingers at the twisted spoon and it bends back into shape. “Don’t worry about it, nii-san.”

Hinata opens and closes his mouth, but nothing comes out. “You look like a goldfish,” Tobio tells him. “Just sit down, dumbass.”

“Language, Tobio, there are  _ children _ present,” his mother scolds, then turns to Ritsu. “And when did your powers develop, Ritsu-chan?”

“Just a few months ago,” Ritsu answers, still smiling. He reminds Hinata of their class rep, always very careful to seem like a nice young man. 

Hinata pokes Tobio in the side. “Are you going to explain any of this, or…?”

“No,” Tobio says. Hinata glares at him for a solid thirty seconds, and Tobio relents. “…My cousins are espers. They can see spirits and move stuff with their minds.”

“That is the coolest thing I’ve ever heard of in my entire life.”

Shigeo and Ritsu exchange a look. “It’s not that great,” Shigeo says softly, staring at his spoon again.

Hinata and Tobio go out to the yard to toss a volleyball around after dinner. Tobio’s cousins come outside too. Shigeo’s talking to someone on the phone. Ritsu brings a book he explains was summer reading homework.

“Nii-san has a part-time job now,” Ritsu explains. “I think he forgot to tell his boss he was going on vacation, but he definitely needed one, after all that stuff that happened. Reigen-san gets worried.”

Hinata leans forward, eyes sparkling with the promise of an interesting story. “What kind of stuff?” 

Tobio throws the volleyball at Hinata. “Stop bothering them.”

Hinata sticks his tongue out at Tobio.

“How many espers are there?” Hinata asks, diving to the ground to receive the ball.

Shigeo, done with his phone call, is now sitting on the porch and watching the Karasuno kids play. “I don’t know,” he says helpfully.

“Shigeo-kun, are you sure you don’t want to try playing with us?” Hinata asks cheerfully. “It’s fun!”

Shigeo picks up a stick from the ground and observes a beetle crawl along it. “No thanks.”

“Ritsu-kun?”

Ritsu gestures towards his book.

“Your cousins are kind of boring, huh,” Hinata whispers to Tobio. “But I guess it makes sense since they’re related to you— _ don’t kick me, Bakageyama— _ ”

Hinata refuses to give up on making friends with Kageyama’s weird cousins. Hinata’s like that, Tobio thinks, befriending anyone and anything in his path. Hinata just…likes people. Tobio’s always wondered how that worked. 

Hinata throws the volleyball as high as he can for no reason, and it misses the mulberry tree in the Kageyama’s yard to fall back into his arms, glowing blue. “Ah. Thanks. So, younger Kageyamas, tell me about yourselves!”

They look at each other awkwardly for a moment. “Well, Ritsu’s super cool,” Shigeo offers. “He’s popular and athletic and smart and in Student Council.”

Hinata turns to Tobio. “Are you sure you’re related?”

“What is that supposed to mean?” Tobio swipes at Hinata, who dodges with practiced ease, cackling.

“Nii-san is much more powerful than I am, when it comes to psychic abilities. I just developed them a few months ago.” Ritsu frowns and looks to the side, and Hinata gets a sense there’s more to the story than that.

“Does it have to do with that … needing a vacation stuff you mentioned earlier?”

The siblings look at the ground, not answering.

“If they don’t want to talk about it, they don’t have to, dumbass,” Tobio says.

Hinata doesn’t get another demonstration of the siblings’ esper powers until he messes up a receive and sends the ball hurtling towards Shigeo’s head. Shigeo looks up and all of the boys watch as the ball glows blue and hovers several feet above the ground, before gently floating into Hinata’s arms like a meticulously aimed balloon.

There is an awkward silence.

“Sorry, Shigeo-kun!” Hinata manages. Part of him wants to keep pelting the kid with objects to see what happens, part of him is worried what Shigeo will do if he gets pissed off.

“Don’t,” Tobio says to Hinata, like he’s reading Hinata’s mind. Which wouldn’t be surprising at this point, since his cousins can do things like stop volleyballs by thinking about it. 

“Are you  _ sure  _ you don’t want to try playing volleyball?” Hinata wheedles.

Shigeo blinks slowly. “No thank you.”

“I don’t think that would be a very fair game,” Ritsu calls out, without looking up from his book. 

“But it would be interesting!”

The sun is setting now, painting the yard with shades of orange and purple.

“I should probably be getting home,” Hinata says, “my mom doesn’t like it when I bike in the dark.”

“You go home after practice in the dark all the time,” says Tobio.

“She still doesn’t  _ like _ it!” They go back in the house, the cousins following behind like quiet, polite ghosts.

“Thank you for your hospitality, Kageyama-san!” Hinata exclaims, bowing low to Tobio’s mother. “It was nice to meet you, Shigeo-kun, Ritsu-kun!”

“Nice to meet you too, Hinata-san,” Ritsu replies, smiling slightly. Shigeo just nods.

“See you tomorrow,” Tobio says.

Hinata blinks. “What’re we doing tomorrow?”

“We still haven’t finished the math homework, dumbass.” 

“Oh, yeah.” Hinata finishes lacing his sneakers and jumps up again with a grin so blinding Tobio has to look away. “Maybe next time we can teach your cousins how to serve! Powers or no powers.”

Shigeo looks mildly ill at the prospect, but Ritsu’s polite smile is unchanged. “We’re looking forward to it,” Ritsu answers for the both of them.

At the study session the next day, Hinata reenacts his encounter with Tobio’s relatives in his usual bombastic manner. “And then Kageyama’s cousin was like  _ whooosh  _ and the volleyball was like  _ nyoom  _ and then—”

“Please learn to speak Japanese,” Tsukishima interrupts. He glares pointedly at Hinata’s half-finished kanji worksheet, eyebrows raised. 

Hinata pouts at him and sits back down reluctantly. “Anyway, it was really cool! Shigeo-kun can do super cool stuff!” Tobio didn’t tell him the esper thing was a secret, exactly, but Hinata figures he shouldn’t go around telling everyone about supernatural powers.

“I’m glad you all had fun!” Yachi beams.

“I can come over again today, right?” Hinata demands, gesturing at Tobio with a pencil.

“Sure, whatever.”

Tobio and Hinata work in silence for a bit while Tsukishima and Yamaguchi have their own conversation in a corner. Yachi jumps up to bring everyone more snacks. Hinata pokes Tobio with the eraser end of his mechanical pencil. “Thanks again for letting me meet your family,” Hinata says quietly. “It was fun. I mean it.”

Tobio stares at the glass tabletop like he’s trying to melt it with his eyes. “It’s not that important. Dumbass.”

The sky is blue, Kageyama Tobio’s cousins have supernatural powers, and Hinata’s a dumbass. All is as it should be.

**Author's Note:**

> creds to gio who probably does not remember putting this idea into my head many months ago, I finally finished the mp100 anime and then sat down and started writing this  
> also thanks to jessie whose intense love for mp100 Inspired me   
> talk to me on [tumblr](http://cubistemoji.tumblr.com/) or [twitter](http://twitter.com/mashazart/)  
> 


End file.
